#include <stdio.h>
int main()
{	
	int n = 0, x = 0, y = 0;
	scanf("%d %d %d", &n, &x, &y);
	if ( y % x == 0 ) {
		n = n - (y / x);
	}
	else {
		n = n - (y / x) - 1;
	}
	
	if ( n < 0 ) {
		n = 0;
	}
	printf("%d", n);
	return 0;
}

